Field of the Invention
The present invention relates to a stepping motor, and more particularly, to a stepping motor in which a moving part such as a nut is provided at a lead screw.
Discussion of Related Art
A stepping motor is used to precisely control an extent of mechanical movement, and may be digitally controlled by a pulse. Due to this reason, the stepping motor is used for adjustments of a direction and an angle of a vehicular lamp or optical pickup of an optical disk driver which require precise control.
In a stepping motor, a lead screw inserted into a bracket rotates and straightly moves a moving part such as a nut, thereby controlling an extent of movement. However, since the moving part is coupled only by the lead screw, the moving part may be easily moved by an external impact and difficult to be precisely controlled.
To resolve this, a configuration in which a guide protrusion is formed at a moving part, and a guide structure which guides the guide protrusion is formed at the bracket is being suggested.
Here, a guide configuration such as a guide slot is configured to come in contact with both of top and bottom portions of the guide protrusion to prevent the moving part from moving.
However, such a guide configuration may be difficult to manage flatness of the guide slot and have a great friction load due to a great friction area between the guide slot and the guide protrusion.